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  Topic Review (Newest First)
05-16-2013 09:37 AM
Re: Weather Forecasts (Chesapeake in this case)

Thank you all again for the valuable information provided. I am adding it all to my repertoire of pre-sail research sources.

Gary, I think you hit the nail on the head. Here is my experience from Monday afternoon:

Left the slip at 3pm, winds were very light (no windspeed indicator on the boat) out of the NW. We expected some more winds and waves once past the jetties, but were disappointed. Once past G1 out of Herrington Harbor North we turned toward shore to raise the reefed main, followed by the jib, fully unfurled.

We made at most 3 knots and barely a hair on our heads would have been disturbed (we were wearing hats) by the sorry excuse for wind. As this was going on for a good 30 minutes we decided to let out the reef.

By the time we turned E out of Herring Bay at R2, winds had increased slightly, and we sailed very comfortably and relaxed on a reach toward G1 in the middle of Herring Bay without a destination in mind.

Eventually, we decided to turn around and get back to watch the hockey game. At this point the winds had picked up further with gusts that prompted the boat to point upwind, which is fine, but it was beginning to feel uncomfortable for my crew every time a gust hit and made us heel unexpectedly.

By the time we tacked our way back around R2, trying to sail 0 True, the wind was now constantly blowing to the point where I wish I could have reefed again. Plus it was changing direction mostly to the NNW, which quickly made us decide to take down the sails and motor back.

By the time we got to the jetties, we were heeling a bit even without any sails up at all.

Yeah, that's about it. 1/3 creeping along with nary a whisp, 1/3 of perfect sailing, and 1/3 of really working and at times freaking out my crew a bit.

Lessons learned:

1) The Chesapeake is, indeed, unpredictable.
2) Keep the reef in when sailing during an SCA - you never know when it'll hit.
3) Take it easy. If you wanted to get anywhere fast you would be on a powerboat.

Anywho - thanks again all!

05-13-2013 10:01 PM
Re: Weather Forecasts (Chesapeake in this case)

Unfortunately, none of the Chesapeake Bay forecasts are very accurate. My best advice, after more than 6 decades on the estuary, take a good look at the tree tops, the cloud movement, then make an educated guess on the side of safety. The bay can be very unforgiving, especially for those who take things for granted, such as the weather forecasts. Keep in mind there are no repercussions for those dispensing bum weather information. And, they never seem to apologize for a lousy forecast.

Good Luck,

05-13-2013 09:45 PM
Re: Weather Forecasts (Chesapeake in this case)

I've seemed to notice the reliability of SailFlow has gotten notably worse, since they updated their site. And, I don't really like their new GUI either. Too bad. It was a real go to resource for me.
05-13-2013 05:13 PM
Re: Weather Forecasts (Chesapeake in this case)

try the cbibbs bouys they are still working and give you now conditions. you can down load to a smart phone or I-pad. They are called smart bouys on the app store
05-13-2013 12:24 PM
Re: Weather Forecasts (Chesapeake in this case)

Thank you all for the additional feedback and info. As for the localized SCA parameters - I learned something new again. I do Google just about everything, but this didn't pop up.

Three hours to sailtime now, so we'll see how it goes. I do like the idea of putting up the full main and gauging the jib. Thankfully, I can just furl/unfurl the genny as needed. It'll help to have crew onboard this time, too. I took out a Catalina 27 on Cinco de Mayo, and that was a bit of a pain to single-hand that day.

For what it's worth, I'll post how it went afterwards - assuming I remember to do so, as the post-sail activities will involve watching the Caps in Game 7 at Calypso. (Sorry, Rangers fans)

Thanks again!

05-13-2013 12:24 PM
Re: Weather Forecasts (Chesapeake in this case)

I have found that to be most accurate for wind/ weather forcasting. Uses a variety of data
05-13-2013 12:24 PM
Re: Weather Forecasts (Chesapeake in this case)

Good point. Here are two very different examples of SCA, both near the mouth of the Potomac, one gusting and one with waves:

Gusting from the South (small waves near southern shore of Potomac):

Waves from a prolonged North wind, fairly stead wind in the teens:
05-13-2013 12:13 PM
Re: Weather Forecasts (Chesapeake in this case)

The definition of SCA depends on the area (google it). On the Chesapeake and Potomac it is :

Small Craft Advisory

Small Craft Advisories are issued for the Tidal Potomac River and the Chesapeake Bay when one or both of the following conditions is expected to begin within 36 hours:

1) sustained winds of 18 knots to 33 knots


2) frequent gusts (duration of two or more hours) between 18 knots and 33 knots.


3) waves of 4 feet or higher

Second, you really need to use NOAA wind speeds. Yes, this was a minimal SCA. Additionally, your feeling on the subject might be different at the mouth of the Potomac in a sailing dingy with a green crew. It is just an advisory. For cruising boats it mostly means clear the table, just in case.
05-13-2013 12:12 PM
Re: Weather Forecasts (Chesapeake in this case)

Originally Posted by EuroboyDC View Post
- NWS says there is a small craft advisory in effect through late tonight from Sandy Point to North Beach. To my recollection, an SMA is triggered between 22-33 knot winds...
As you can see, there is a good degree of contradiction here. Which model should I trust?
There is no contradiction. The NOAA weather radio Small Craft Advisory is issued in advance of the SCA conditions and does not necessarily reflect current conditions. The weather synopsis portion of the forecast informs us that high pressure is steadily moving into this area through tonight. The wind speed range is predicted to increase another 5 knots this afternoon and evening from 10-15 knots to 15 to 20 knots - that is the basis for the SCA.

Originally Posted by EuroboyDC View Post
Also, given the circumstances, would you go out with a reef on a 30' O'Day 302 or just go full canvas?
I would not head out with a reef in the main in those conditions, but I would be more conservative in my jib choice with predicted increase in wind speed.

I head out plannng to use a full main, usually, then I judge the headsail by the conditions. You can always ease the main to reef once the jib is up. I usually rig everything in the marina for ease of possible use: jib sheets, whisker pole, spinnaker pole, spin sheets, turning blocks, unless I am only going for a short sail. On a number of occasions, it gets stowed without being used that day.
05-13-2013 12:11 PM
Re: Weather Forecasts (Chesapeake in this case)


Small craft advisory numbers are localized. So may be one thing outside of the Chesapeake, they may not be the same in the Chesapeake area. Each local NWS station around the country determines what they consider the wind speed/wave height combination should be for a SCA in their specific area.

At least, that's what was told to us at the weather seminar I took with a NWS forecaster.
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